Tool-mounting arbor



G. J. TOWLE TOOL-MOUNTING ARBOR Filed Sept. 23, 1949 Oct. 20, 1,953

. INVENT OR GEORGE JJowLE ".gw ATTORNEY Patented Oct. 20, 1953 UNITED STATES PATENT OFFICE TOOL-MOUNTING ARBOR George J. Towle, Walnut Creek, Calif. Application September 23, 1949, Serial No. 117,306

2 Claims.

The invention relates to an arbor for mounting rotary tools on a drive shaft therefor.

-An object of the invention is to provide an arbor unit of thecharacter described which is particularly adapted for its mounting on and within a tubular shaft end. Another object is to provide an arbor of the character described which is particularly adapted for mounting on the power take-off shaft of a portable electric motor of beater-operating or other types.

' A further object is to provide for a particularly ready and true mounting of the arbor on a tubular shaft end.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will-beset forth or be apparent in the following description of typical embodiments of the invention, and in the accompanying drawings, in which, i v

Figure 1 is an elevation showing one embodiment of the arbor as mounting a sander disc on the driven shaft of a dismountable motor of atype commonly used with beater heads.

Figure 2 is an enlarged fragmentary axial section of the installation of Figure 1.

- Figure 3 is an axial section showing the arbor of Figure 2 in condition for its removal, or its attachment, with respect to the tubular shaft end to which it is shown fixed in Figure 2.

Figure 4 shows the elements of the tool mount f-Figures 1 and 2 in axially disassembled relation;

Figure 5 is a section taken at the line 5-5 in Figure 2.

Figure 6 is a partly sectional elevation of a bushing sleeve which is arranged for use with the arbor assembly of Figures 1 to 5.

Figure 7 is a partly sectional view corresponding to Figure 2 and showing the bushing sleeve of Figure 6 in use.

Figure 8 is a section taken at the line 8+8 in Figure 7 duction gearing are provided in a usual assembly in the household food-beater art. The motor unit 16 is arranged for use while mounted or dismounted with respect to a base-carried standard I8 which has been indicated in dotted lines. The sanding disc I4 is shown as provided with a threaded stem 14' for use in mounting it on the present arbor, may mount a wool buffing or polishing element (not shown) in generally enclosing relation to it, and is consideredto represent any tool, or tool chuck, having a mounting stem corresponding to the stem 14' of the sanding disc 14. Also, the motor unit 16 is shown as generally representing any motor providing a tubular shaft end which is adapted or adaptable to mount a present arbor assembly. It will now be noted that the motor shaft I 5 has a tubular terminal portion l5 disposed in a tubular extension I9 of the casing I! and terminating substantially at the extremity of said extension, and that the bore of the shaft end I5 is arranged to receive an element 22 of an arbor assembly 2| comprising the element 22 and an element 23. The element 22 is tubular and has a radially-expandable forward portion 24 of a size for freely entering the bore I5" of the shaft end [5' when it is unexpanded. The rearward portion 25 of the element 22 is somewhat larger than the shaft bore 15'', and is connected with the forward portion 24 of the element by a comcally tapered portion 26.

A plurality of slots or kerfs 24' extend longitudinally into the portion 24 of the element 22 from its forward end for substantially its full length, and the forward end of the portion 24 is formed to provide a forwardly tapered bore portion 24" which is smaller than the remainder of the bore of the element. The rearward portion 25 of the element 22 has its bore portion interiorly threaded from its free end. Essentially, the element 22 is so proportioned that its tapered portion 26 may engage the extremity of the shaft end I5 to limit the insertion of the element 22 within the shaft bore l5" while centering the element thereat, the relation being brought out in Figure 3. Preferably, and as shown, there are four slots 24' evenly spaced about the portion 24, and said portion has flattened side portions across the slots whereby the portion 24 may be installed in a shaft bore of either square or circular cross-section.

As particularly shown, the element 23 comprises a forward stem portion 21 and a rearward stem portion 28 extending oppositely from a relatively large cylindrical portion 29 having its peripheral surface knurled to facilitate its turning by a persons fingers, said stem portions being coaxial. The forward portion 21 of the element 23 is provided with threads 21 adjacent the portion 29 for complementarily engaging the bore threads of the rearward portion 25 of the element 22, and is provided at its forward end with a conically tapered tip 21" which is arranged for wedgedly operating in the bore portion 24" of the element 22 as the stem 27 is screwed into the portion 25; the arrangement is essentially such that the advancement of the stem 21 through the element 22 is arranged, by reason of the threaded engagement of the elements to spread the tongue partsof the element defined between the slots 24 into a gripping relation with the bore t5", and so provide a means which is releasably reactive between the elements to fix the assembly 22-23 to the shaft end I5, the relation being brought out in Figure 2.

The present arbor assembly 2| is arranged to threadedly mount a coupling sleeve 3| on the threaded stem portion 28; of its element 23, and the sleeve 3| may in turn threadedly receive the stem M of the sanding dis-c M or another rotary tool from its other end for mounting the tool on the sleeve. On the other hand, the exteriorly threaded stem 28 of the element 23 may directly engage a complementary threaded base member of a tool chuck or a tool, for mounting the chuck or tooldirectly on the same element. Various types of rotary tools may, of course, be mounted on the present arbor, such tools, including, besides the sanding disc shown, tools for guiding and/or buffing and/or waxing and/or polishing, drills, chucks for drills and/or reamers, fans, flexible shafts, and other rotary elements which are operative with the available motor power.

Figures 6 to, 8 inclusive disclose an arrangement by which the present arbor assembly 2|, comprising the elements 22 and 23-, is arranged for rmounting on an extension IQ of a motor casing H in which the shaftbore is larger than the rear portion 25 of the element 22. In this case, a bushing sleeve. 32 is provided for fitting over the portion 24 of the. element togrippingly increase the effective diameter thereof with respect to the receiving shaft bore. Accordingly, the bushing sleeve 32 is provided. with. slots 33 extending from its forward end, is provided at its rearward end with a radial bead 34.for engaging the free end oftheshaft to limit itsinsertion Within the shaft bore, and. has itsbore uniform except at its rear end portion which is conically tapered for complementary engagement by the conical exterior of the portion 26 0f the element 22. It will thus be understood that the bushing sleeve 32-, which may beof any required thickness, provides for the mounting ofa present arbor in a larger shaft bore than that of the shaft.- l5. 7

The embodiment of-Figures 9 to 11- inclusive discloses anarbor assembly 4| comprisin elements 42 and 43 and 44 engaged in order and having the element 42 provide a forward expansion portion for securing the-assembly to the shaft end |5'. In the present instance, theelement 42 has a longitudinally slotted forward portion 45 provided with longitudinal slots- 45' and extending from anintermediate tapered portion- 46 which in turn extends from an enlarged cylin drical and externally knurled portion 41 ata radial shoulder 48 in itsbase. In the present arbor assembly, the element 42, which corre-; sponds generally-to the element 22 of the first embodiment, is arranged to have its conically tapered portion 46 engage the end of the shaft bore l5 as a centering means for the element. The bore of the element 42 is uniform and receives therethrough the element 43 which has an intermediate portion 49 of uniform size, a forward conically flaring end portion 50, and an externally threaded rear portion 5| for engaging the threaded bore of the element 44 which, in the present instance, has the same form and threaded-bore size as the bushing sleeve 32 of the first embodiment.

When the present arbor assembly 4| is to be installed or removed from the bore of a shaft end, the conical head 50 is arranged to be disposed forwardly of the forward end of the element 42, and a turning-up of the element 44 on the part 5| of the element 43 is arranged to draw the head 50 into the forward end of the portion 45 of the element 42 to wedgedly spread the portion for fixing the arbor to the shaft; it will be understood that the bore-gripping action of the portion 45 is provided by reason of the thrustof the element 44 against the rear end ofthe element 42 as the latter element is turned up on the .extend radially from the portion 49 of the element; 43' near its head 59 and slidably engage in the slots 45 for preventing a rotation of the element in the element 42 by reason of a turning of the element 44. The threaded bore of the element 44 has an unused rearward portion which may receive the mounting stem l4 of a sanding disc I4, or a corresponding mounting stem for another tool or a tool-carrying chuck. Since the element; 44 comprises an operative part thereof, it will be understood that the present arbor assembly 4| comprises a minimum of three elements 42 and 43 and 44, in. contradistinction to the arbor assembly 2| which requires solely the two elements 22 and 23-.

From the foregoing description taken in connection with the accompanying drawings, the advantages of the present tool-mounting arbor will be readily understood by those skilled in the art to which the invention appertains. Whilev I have described the principle of operation, to-' gether with arrangements which I now consider to comprise preferred embodiment thereof, I desire to have it understood that theshowings are primarily illustrative, and that such changes and developments may be made, when desired, as fall within the scope of the following claims.

I claim:

1. For use with a driven mandrel shaft having a tool-attaching end portion providing an axial bore, a tool-mounting. arbor comprising a tubular element having a radially expansible end part extendable into the shaft bore in complementary relation thereto for its terminal grippin expansion therein and having an intermediate part formed and arranged: for its complementary centering engagement in the free end of the b'ore, a member longitudinally adjustable in the bore of the tubular member for grippingl'y expanding the first part in. theshaftborewhile said intermediate part of the element isoperatively en-z gaged therein, and a releasable means directly reactive between the element and the memberto positively eifect and maintain the operative disposal of the second member.

2; For use with a driven mandrel shaft having a tool-attaching end portion providing an axial bore, a tool-mounting arbor comprising a tubular element having a radially expansible end part extendable into the shaft bore in complementary relation thereto for its terminal grippin expansion therein and having an intermediate part conically expanding from the base of the expansible part for its wedged centering engagement in the free end of the bore, a member longitudinally adjustable in the bore of the tubular member for grippingly expanding the :fullyinserted first part in the shaft bore while said intermediate part of the element is operatively engaged therein, and a releasable means reactive between the members to positively effect and maintain the operative disposal of the second member.

GEORGE J. TOWLE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,889,571 Redinger Nov. 29, 1932 2,204,508 Matthies June 11, 1940 2,359,532 Searle Oct. 3, 1944 2,406,128 Billman Aug. 20, 1946 2,434,863 Parkhill Jan. 20, 1948 

